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External Fujitsu MO Drive (Custom Case)
Posted by: jmacz on 2025-02-13 21:52:45
Got bored, so decided to convert one of my internal SCSI Fujitsu magneto optical drives into an external drive.

Rather trivial, just needed to figure out the power situation and then convert from an internal 50 pin connector to a DB25. These MO drives only need +5V (the 12V is not connected on the molex power connector on the drive) so it's straight forward.

I decided to combine a SCSI adapter, a 5.5mm barrel plug port, a small set of dip switches for the SCSI ID, all onto a single PCB design and get it made via jlcpcb.

IMG_9438.JPG

Then the fun part was designing an enclosure. I wanted it to fit the aesthetic of the Macintosh II series. So I came up with this design:

frame-bottom.jpg

That's the bottom plate that the MO drive and PCB will mount to. It matches the ribbed design of the Macintosh II case. And then here it is with the top.

frame-top.jpg

Then printed it out on my 3D printer in PLA. The walls are thick (2mm) so even with PLA, the case is really solid/sturdy. With the bottom part printed out and components soldered onto the PCB, I decided to test it out:

IMG_9440.JPG

Everything fit nicely. The power brick is a 5V 4A adapter and it works fine. The MO drive specs shows a peak current requirement of 2.5A so it should be fine. I went with dip switches for the SCSI ID as I didn't have much luck finding a reasonable rolling SCSI ID selector. I had left one dip switch to enable/disable termination but that was dumb (I wasn't thinking) since I only have one SCSI port so that makes no sense since it needs to always be enabled as it will be the last device in the chain.

IMG_9452.JPG

And here it is fully assembled from various angles. Yes, I cracked part of the top as I was about 0.5mm too narrow on the hole I made for the power switch. 😕 I will need to fix that later with a reprint at some point.

IMG_9455.JPG

Another shot.

IMG_9453.JPG

And another.

IMG_9454.JPG

I will probably make a reprint of the case (to fix that crack near the power switch) and then paint it my usual gray color to match my refinished Macs.

I still do have 4 of the PCBs available. I might make one more with a 2.3GB drive (the one pictured above is a 640MB drive).
Posted by: ArmorAlley on 2025-02-13 22:57:47
Would USB work to power it? It has the voltage but I'm not sure about the amperage.
Posted by: obsolete on 2025-02-14 10:12:33
That's beautiful! Fantastic work.
Posted by: jmacz on 2025-02-14 11:08:11
Would USB work to power it? It has the voltage but I'm not sure about the amperage.

I'm not sure. I was under the impression USB taps out at less than 2A?

But I'm fine with the power brick. No different than what I have to deal with for my Zip drives.
Posted by: Unknown_K on 2025-02-14 12:11:03
That turned out pretty nice. I find external SCSI drives get more use since I have a bunch of SCSI equipped machines.
Posted by: MrFahrenheit on 2025-02-16 10:19:25
Wow! That’s amazing!!

Great work!
Posted by: demik on 2025-02-27 03:18:23
Missed that, amazing job!
Posted by: JAG on 2025-04-15 17:45:01
Any plans to make the files available to make the PCB's? I'd like to make one of these. I have a few couple MO drives as well that I'd like to convert.
Posted by: jmacz on 2025-04-15 21:12:37
I wasn't planning on making the files available right now as it doesn't use generic parts. But I have 3 of the PCBs still available as well as some of the components for it. So if you want a small kit (including the non-generic parts) at cost, send me a message and I can get the kit to you. The only component I might not have is the IDC 50pin header (it's possible I have one but I need to check).
Posted by: zefrenchtoon on 2025-04-16 04:37:46
I'm not sure. I was under the impression USB taps out at less than 2A?

But I'm fine with the power brick. No different than what I have to deal with for my Zip drives.
Using USB-C Raspberry Pi 5 PSU, it should be fine I think


Very nice and interesting project BTW 🙂
Posted by: jmacz on 2025-04-17 20:56:37
I wasn't planning on making the files available right now as it doesn't use generic parts. But I have 3 of the PCBs still available as well as some of the components for it. So if you want a small kit (including the non-generic parts) at cost, send me a message and I can get the kit to you. The only component I might not have is the IDC 50pin header (it's possible I have one but I need to check).

IMG_9767.JPG

I've got a few of these.
Posted by: mg.man on 2025-05-05 10:39:06
I've got a few of these.
Nice - PM sent if not too late!
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